弹体冲击防弹头盔致颅脑非贯穿性损伤机理研究

防弹头盔作为保护士兵的最后一道防线，其防护性能的好坏直接影响士兵的生命安全。当高速高能弹体冲击防弹头盔时，即使头盔能抵挡弹体的穿透，其冲击动能产生的头盔变形与冲击波作用仍会对士兵颅脑造成极大伤害，甚至致命。然而，其造成的非贯穿性颅脑损伤机理尚不明确。本课题拟采用生物材料实验获得高应变率下颅骨、脑组织的材料动态本构关系及力学性能，采用长白猪实验获得动物的生理响应及损伤耐受极限，采用颅脑物理模型进行弹体冲击实验，将物理模型的力学响应与动物实验得出的损伤程度建立量级关系。再结合数值模拟获得弹体冲击载荷下颅骨及颅脑组织的接触力、应力-应变、加速度，颅内压等，理解冲击波在颅骨、脑脊液-脑中传播产生的反射与折射、冲击振动等综合作用产生的颅内响应，建立起生理特征、生物组织损伤耐受与力学参数之间的关系，获得弹体作用力与冲击波在颅脑内的传导规律与损伤量级关系，揭示非贯穿性颅脑损伤的致伤机理。

The performance of bulletproof helmets which are regarded as the last line of defense to protect the lives of soldiers directly affects the soldier safety. When a high-speed and high-energy bullet impacts the bulletproof helmet, the deformation and shock wave generated by the impact kinetic energy will cause great damage to the soldier's brain and even threaten life, even if the helmet can resist the penetration of the missile. However, the non-penetrating brain injury caused by the impact contact force and shock wave conduction in the brain has not been thoroughly studied and the injury mechanism is still unclear. In this project, the dynamic constitutive relations and mechanical properties of skull and brain tissue under high strain rate are investigated by biomaterial experiments. Impact test results using both landraces and physical head models with precise constitutive relations are used to establish the orderly relationships between the damage degree of the physical models and the mechanical response and the damage level obtained from animal experiments. Then, the biomechanical response of the brain under bullet impact loading is obtained combined with analysis using a finite element brain model. The mechanical response and transmission law of contact force and shock wave in the skull and brain, and the key factors affecting the severity of brain injury are analyzed in this project, which could reveal the mechanism of non-penetrating craniocerebral injury caused by the combined action of contact force and shock wave conduction in bullet-to-bulletproof helmet impacts.